"We're not thinking big enough," Mika said. "If Dzwell is going to take over the world in just a few years then he needs to be stopped. And with this Stone, not only do we have a way to stop him, we have a way to make it so that he never did any of his evil deeds in the first place!"
"Yeah," Audrey agreed, "then none of my friends would be tuna!"
Mat tried to protest, "No, you can't change reality like that, you have no idea what the consequences could be, and any consequences could be possible--"
Mika ignored him. He took the Stone out of the protective bag, held it in his hand, and looked at it as he spoke. "I want to make it so that Dzwell isn't trying to conquer the world. A reality where Dzwell has always been good instead of evil. Dzwell the Good."
Mat shouted, "NO!" but it was too late. The Stone glowed brighter and brighter and then there was a huge flash of light that washed over the whole tavern and beyond. Reality twisted and distorted, and everyone found themselves changed.
One second, Dzwell (or Jurl) was a mare being penetrated by a stallion in the stable. The next, he was a human man sitting far away in a lavishly-appointed study at the top of a tower, and despite the odd sore sensations around his crotch he found himself overwhelmed by feelings of compassion and charity and brotherly love, the urge to do right, help others, and make the world a better place, urges and feelings that felt oddly foreign and yet also totally familiar because he could remember always having them.
The mare that Ed was mounting suddenly disappeared and he fell forward onto his front hooves, but he was so close that he orgasmed anyway, shooting away his humanity as pleasure overwhelmed thoughts and memories and the weight of equine instincts settled over his increasingly dull and simple mind. Ed's equine body grew taller and swelled with muscle as he gained the build of a warhorse fit to carry a knight. There was no mare there so he hadn't just had an orgasm, and instead he munched on hay and waited contentedly for his Rider to return.
Mika also felt himself growing bigger, taller, and more muscular, and looked down to find a strapping body covered in metal armor. He was confused and tried to cast a spell, but then realized that he didn't know magic. In fact, he knew a lot fewer things now, though he had learned how to handle weapons expertly. He had spent his years sparring, riding, and fighting instead of reading books inside, and while he wasn't dumb he was much less smart than he had been. He was being rewritten with a new life as a knight instead of a wizard, with new memories and a new personality: brave and kind and chivalrous but also cocky and arrogant and reckless. He was Sir Mika, a knight of the Order of Dzwell the Good, and he has been sent here by the Order on his first quest to combat the forces of evil by finding and retrieving the Shifting Stones of Sharn (the one he was holding disappeared from his hand), along with his trusty steed Ed and his wizard companion Matteus.
With a pop, Mat was suddenly a non-flat human man again, although naked and lying on the counter. Another pop and he was fully clothed, standing beside Sir Mika. He was indeed a comely man and looked rather similar to what Mika had looked like, in the last reality, though a few years older: handsome, well-groomed, and somewhere between slender and scrawny. He still remembered working for Dzwell, but now Dzwell was a good wizard instead of an evil one, and Mat hadn't worked with him (or been used as a rag by him) for nearly so long.
Unbeknownst to everyone, including himself, the original Jurl had been transformed into a chair in the tavern when Dzwell took his place. He too was now a human man again, with no recollection of anything that had happen, and stood all gruff and heavyset behind the bar. In the next room, Jess the barmaid clutched her head as she forgot about ever being Traskol the barbarian.
Audrey felt a familiar shrinking sensation, and her eyes widened in panic as she looked down at the scrawny, naked, filthy body of a young stableboy. She tried to run, fight, panic, anything to keep her from being Aubrey again, but it was no use. The familiar mental onslaught began, filling her... his mind with memories of life as an urchin and stableboy. Audrey the female warrior faded and evaporated as Aubrey's dumb, goofy, submissive mindset took hold. Blinking, Aubrey found himself in the stables, and set about his chores. He groomed the warhorse there without thinking, and Ed enjoyed the attention with a similar lack of thought.
Back in the main room, the new reality clicked and settled into place. Sir Mika blinked, disoriented for just a moment, and then addressed the man behind the bar. "Innkeeper," he said in a voice that he did not realize was deeper and more commanding, "my companion and I seek the Shifting Stones of Sharn, in the name of the Order of Dzwell the Good. Are you able to aid us in our quest?" Mat rolled his mischievous green eyes at his young companion's overdone chivalry.